(1) Field of the Invention
The present invention relates to a method for wiring to form a coil and a coil apparatus formed thereby, in which a wire is inserted into a hole of a workpiece, such as a cove, and is wound around the workpiece to form the coil.
(2) Description of the Background Art
For example, when a magnetic disc read or write head is manufactured, it is necessary to form a coil with wire wound around the core of the head. The wire is inserted into a small hole formed in the core and, then, the wire is wound around the core to produce the winding. The outer surface of the wire s formed of an enamel-coated insulating material, whereby electrical leakage can be prevented.
However, if the insulating coating of the wire is damaged due to contact of the insulating coating with an edge of the core constituting the workpiece, electrical leakage occurs between the wire and workpiece. To prevent such leakage, the possible number of turns which are inserted into the small hole and wound around the core must be limited if the thickness of the enamel-coated insulating material is made thicker.
To eliminate such leakage problems, tape has been wound on a corner of the workpiece and the winding is carried out thereon. However, the small hole through which the wire is inserted becomes smaller due to the thickness, width, and/or cross sectional area of the tape, and the possible number of turns of the winding must again be limited. In addition, since a process of winding the tape is added, the total cost of manufacturing the coil apparatus is increased. In addition, when the wire is softly or gently wound around the core (work) under light pressure in order to weaken friction between the wire and the edge, the possible number of turns of the winding becomes reduced. Another solution may be considered in that the edge formed on each corner of the work may be chamfered or polished to produce a curvature. However, this method is difficult to put into practice in terms of processing technology and practical expenditure.